PIEAS Science General MCQs

After a 20% increase, the quantity becomes 120% of the original.
The required reduction is 20/120 × 100 = 16⅔%.

The greatest common divisor of 18 and 24 is 6.
Dividing both terms by 6 gives 3/4.

Convert 2/3 to sixths: 2/3 = 4/6.
Then 4/6 + 1/6 = 5/6.

Convert 1/4 to 2/8.
Then 7/8 - 2/8 = 5/8.

Multiply numerators and denominators, then simplify.
(3 × 10)/(5 × 9) = 30/45 = 2/3.

Dividing by a fraction means multiplying by its reciprocal.
Thus, 4/7 × 3/2 = 12/14 = 6/7.

The decimal 0.375 equals 375/1000.
Dividing numerator and denominator by 125 gives 3/8.

Divide 7 by 20 or convert the denominator to 100.
Since 7/20 = 35/100, the decimal is 0.35.

Twenty-five percent is one quarter.
One quarter of 240 is 240 ÷ 4 = 60.

The increase is 20 on an original value of 80.
The percentage increase is 20/80 × 100 = 25%.

The decrease is Rs. 75.
The percentage decrease is 75/500 × 100 = 15%.

Let the number be x, so 0.40x = 72.
Dividing by 0.40 gives x = 180.